1. Field of the Invention
This invention relates to systems and processes for applying chemical solutions, colors and patterns to fabrics and for developing and fixing the chemicals in a continuous operation within a common chamber to provide a dyed, or printed and fully processed material.
2. Description of the Prior Art
In the past, it has been known to use batch-heat development of single large rolls of fabric sealed in separate steam chambers each containing one roll. This individual arrangement is very cumbersome and inefficient with respect to energy usage, requires excessive time, space and handling, and is also quite costly. In addition, the process results in the occurrence of undesired swelling and uneven exposure.
Wet fibers being treated and developed normally swell when subjected to heat and steam in order to open intermolecular spaces to permit entry of dyes and other chemicals. Steam chambers containing single rolls hold the rolls for several hours and may require one hour or more just to feed the fabric in. As the roll is heated to the desired temperature, the inside of the roll tends to swell, while the outside does not expand and acts as a tight wrapping. This can cause undesired squeezing of inner layers and migration of chemicals to areas of lower pressure. The result is uneven treatment and unacceptable fabrics. Uneven exposure results from the fabrics being heated in one operation while simultaneously being wound in a roll during the period of treatment. The inside of the roll is then exposed to the chemicals and heat for the full period, while the outside layers have just been impregnated. In a typical operation, the difference in time of exposure to heat and chemicals of the inside to the outside is two or more hours, or a ratio of 1:2. This differential in treatment may result in fabric which is unacceptable.